garthsundem writes: "If you shake your head at this news, Cambridge scientists can now predict the path of your ponytail swing. Really: the "Rapunzel Number" helps mathematicians calculate the effect of gravity relative to hair length, and in combination with other factors like the coefficient of human hair curviness, helps researchers predict the shape of any ponytail. "Our findings extend some central paradigms in statistical physics," one of the researchers is quoted saying. Bravo."